About Chac

Chac 2.7.10 requires an Intel Mac running OS X 10.10 or greater.

Chac is a Maya calendar for the Apple Macintosh computer. Many years ago I wrote a Maya calendar program in RPN for my HP 41-C. In 1988 I started programming the Mac with C. One of the First programs I wrote was called Mac Maya. Later I was dissatisfied with it and completely re-wrote it and called it Chac.

Chac is also an archaeoastronomy program. It allows one find the dates of astronomical events that were important to the people of Mesoamerica.

Chac is named after the Mayan rain god (also spelled Chaac and Chak). The same god was worshipped by other cultures with different languages — Tajin in Totonac, Cocijo in Zapotec and Tlalocantecutli (Tlaloc) in Nahuatl. The icon for this program is based on the Mexican version. You can see carvings of Tlaloc on the ruins of many cultures in Mexico with his googly eyes, surrounded with rings that look like glasses. His face is made out of rattlesnakes. His protruding nose is the head of a snake and he has a mouth full of fangs.

There are researchers who have studied the astrological meanings of the Calendar Round but I'm not one of them. I wrote Chac to create a tool that would do all of the calculations correctly. I can't answer questions about the spiritual implications of the Maya calendar. If you're interested in this I suggest that you read Time and the Highland Maya by Barbara Tedlock.